Explain Enhanced/Extended ER diagram.

Enhanced entity-relationship models, also known as extended entity-relationship models, are advanced database diagrams very similar to regular ER diagrams. Enhanced ERDs are high-level models that represent the requirements and complexities of complex databases.

In addition to the same concepts that ordinary ER diagrams encompass, EERDs include:

Subtypes and supertypes (sometimes known as subclasses and superclasses)

Specialization and generalization

Category or union type

Attribute and relationship inheritance

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